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perldelta (1)


perldelta - what is new for perl v5.12.5


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Perl Programmers Reference Guide                     PERLDELTA(1)

     perldelta - what is new for perl v5.12.5

     This document describes differences between the 5.12.4
     release and the 5.12.5 release.

     If you are upgrading from an earlier release such as 5.12.3,
     first read perl5124delta, which describes differences
     between 5.12.3 and 5.12.4.

  "Encode" decode_xs n-byte heap-overflow (CVE-2011-2939)
     A bug in "Encode" could, on certain inputs, cause the heap
     to overflow.  This problem has been corrected.  Bug reported
     by Robert Zacek.

  "File::Glob::bsd_glob()" memory error with GLOB_ALTDIRFUNC
     Calling "File::Glob::bsd_glob" with the unsupported flag
     GLOB_ALTDIRFUNC would cause an access violation / segfault.
     A Perl program that accepts a flags value from an external
     source could expose itself to denial of service or arbitrary
     code execution attacks.  There are no known exploits in the
     wild.  The problem has been corrected by explicitly
     disabling all unsupported flags and setting unused function
     pointers to null.  Bug reported by Clement Lecigne.

  Heap buffer overrun in 'x' string repeat operator
     Poorly written perl code that allows an attacker to specify
     the count to perl's 'x' string repeat operator can already
     cause a memory exhaustion denial-of-service attack. A flaw
     in versions of perl before 5.15.5 can escalate that into a
     heap buffer overrun; coupled with versions of glibc before
     2.16, it possibly allows the execution of arbitrary code.

     This problem has been fixed.

Incompatible Changes
     There are no changes intentionally incompatible with 5.12.4.
     If any exist, they are bugs and reports are welcome.

Modules and Pragmata
  Updated Modules

     B::Concise no longer produces mangled output with the -tree
     option [perl #80632].


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     A regression introduced in Perl 5.8.8 has been fixed, that
     caused charnames::viacode(0) to return "undef" instead of
     the string "NULL" [perl #72624].

     Encode has been upgraded from version 2.39 to version

     See "Security".

     File::Glob has been upgraded from version 1.07 to version

     See "Security".


     The documentation for the "upper" function now actually says
     "upper", not "lower".


     Module::CoreList has been updated to version 2.50_02 to add
     data for this release.

Changes to Existing Documentation
     The perlebcdic document contains a helpful table to use in
     "tr///" to convert between EBCDIC and Latin1/ASCII.
     Unfortunately, the table was the inverse of the one it
     describes.  This has been corrected.

     The section on User-Defined Case Mappings had some bad
     markup and unclear sentences, making parts of it unreadable.
     This has been rectified.

     This document has been corrected to take non-ASCII platforms
     into account.

Installation and Configuration Improvements
  Platform Specific Changes
     Mac OS X
         There have been configuration and test fixes to make
         Perl build cleanly on Lion and Mountain Lion.

         The NetBSD hints file was corrected to be compatible
         with NetBSD 6.*

Selected Bug Fixes
     o   "chop" now correctly handles characters above

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         "\x{7fffffff}" [perl #73246].

     o   "($<,$>) = (...)" stopped working properly in 5.12.0.
         It is supposed to make a single "setreuid()" call,
         rather than calling "setruid()" and "seteuid()"
         separately.  Consequently it did not work properly.
         This has been fixed [perl #75212].

     o   Fixed a regression of kill() when a match variable is
         used for the process ID to kill [perl #75812].

     o   "UNIVERSAL::VERSION" no longer leaks memory.  It started
         leaking in Perl 5.10.0.

     o   The C-level "my_strftime" functions no longer leaks
         memory.  This fixes a memory leak in "POSIX::strftime"
         [perl #73520].

     o   "caller" no longer leaks memory when called from the DB
         package if @DB::args was assigned to after the first
         call to "caller".  Carp was triggering this bug [perl

     o   Passing to "index" an offset beyond the end of the
         string when the string is encoded internally in UTF8 no
         longer causes panics [perl #75898].

     o   Syntax errors in "(?{...})" blocks in regular
         expressions no longer cause panic messages [perl #2353].

     o   Perl 5.10.0 introduced some faulty logic that made "U*"
         in the middle of a pack template equivalent to "U0" if
         the input string was empty.  This has been fixed [perl

  split() and @_
     split() no longer modifies @_ when called in scalar or void
     context.  In void context it now produces a "Useless use of
     split" warning.  This is actually a change introduced in
     perl 5.12.0, but it was missed from that release's

     Perl 5.12.5 represents approximately 17 months of
     development since Perl 5.12.4 and contains approximately
     1,900 lines of changes across 64 files from 18 authors.

     Perl continues to flourish into its third decade thanks to a
     vibrant community of users and developers. The following
     people are known to have contributed the improvements that
     became Perl 5.12.5:

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     Andy Dougherty, Chris 'BinGOs' Williams, Craig A. Berry,
     David Mitchell, Dominic Hargreaves, Father Chrysostomos,
     Florian Ragwitz, George Greer, Goro Fuji, Jesse Vincent,
     Karl Williamson, Leon Brocard, Nicholas Clark, Rafael
     Garcia-Suarez, Reini Urban, Ricardo Signes, Steve Hay, Tony

     The list above is almost certainly incomplete as it is
     automatically generated from version control history. In
     particular, it does not include the names of the (very much
     appreciated) contributors who reported issues to the Perl
     bug tracker.

     Many of the changes included in this version originated in
     the CPAN modules included in Perl's core. We're grateful to
     the entire CPAN community for helping Perl to flourish.

     For a more complete list of all of Perl's historical
     contributors, please see the AUTHORS file in the Perl source

Reporting Bugs
     If you find what you think is a bug, you might check the
     articles recently posted to the comp.lang.perl.misc
     newsgroup and the perl bug database at .  There may also be information
     at , the Perl Home Page.

     If you believe you have an unreported bug, please run the
     perlbug program included with your release.  Be sure to trim
     your bug down to a tiny but sufficient test case.  Your bug
     report, along with the output of "perl -V", will be sent off
     to to be analysed by the Perl porting team.

     If the bug you are reporting has security implications,
     which make it inappropriate to send to a publicly archived
     mailing list, then please send it to This points to a closed
     subscription unarchived mailing list, which includes all the
     core committers, who be able to help assess the impact of
     issues, figure out a resolution, and help co-ordinate the
     release of patches to mitigate or fix the problem across all
     platforms on which Perl is supported. Please only use this
     address for security issues in the Perl core, not for
     modules independently distributed on CPAN.

     See attributes(5) for descriptions of the following

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     |Availability   | runtime/perl-512 |
     |Stability      | Uncommitted      |
     The Changes file for an explanation of how to view
     exhaustive details on what changed.

     The INSTALL file for how to build Perl.

     The README file for general stuff.

     The Artistic and Copying files for copyright information.

     This software was built from source available at  The original
     community source was downloaded from

     Further information about this software can be found on the
     open source community website at

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